Sorry you are having a bad go, but if they are young there is still a lot of time for recovery.
I feel your pain. Not sure how but my girl macrops nymph managed to bend one of her leg/arms that attaches to the claw. You don't really notice it when you look at her but when she would try to walk it would just collapse and she would fall to her claw on that side. She just had her first shedding since the problem developed a few days ago and things are starting to look up. It is still warped slightly but she can now put weight on it. However, at certain angles or if she tries to move to quickly it will still collapse at times. At least she isn't favoring it anymore, so I'm hoping it will continue to improve with each shedding.
At this point however limb deformities seem like such a minor issue to me unless they mess with shedding. All I know is after having a girl with a deformed mouth, some missing limbs or twisted legs seem like a breeze in over all mantis care.